Miliaria crystallina in an intensive care setting.

Drop-like, transient blisters of miliaria crystallina may develop with focal intensity of heat within the skin, such as occurs in tropical climates or during febrile episodes. Miliaria crystallina develops due to a transient poral closure of the sweat duct opening, resulting in obstruction of free flow of eccrine sweat and retention in a vesicle below the skin surface. Dual cholinergic and adrenergic sweat gland innervation is influenced by a variety of medications used in intensive care patients. We present two febrile intensive care patients in whom enhanced alpha-adrenergic stimulation of sweat gland myoepithelia may have led to miliaria crystallina.